MAMMOTH LAKES, Calif. (AP) — Authorities say a 47-year-old man has been arrested on suspicion of killing a woman found in a shallow grave near a California mountain town nearly two decades ago.

When human remains were discovered in 2003 near Mammoth Lakes, officials could only determine the victim was a woman about 30 to 40 years old from southern Mexico.

The Mono County Sheriff’s Office says advances in DNA technology allowed investigators to identify her as Isabel Sanchez Bernal of Puebla, Mexico. The identification led to the arrest on Friday.

The sheriff’s office did not indicate how detectives determined the suspect was involved in the woman’s death.